Tomas Rosicky has retired from professional football, Sparta Prague have announced, with Borussa Dortmund telling ESPN FC he remains an "all-time favourite" at the club.
Rosicky, 37, left Arsenal in 2016 after 10 years in the Premier League to return to the club where he began his career.
"After careful consideration I have realised I am no longer able to fully prepare my body for what the professional football requires," Rosicky said in a statement released by Sparta.
"I would like to thank Sparta for raising me, for being the first step in my career in big clubs, and for allowing me to say goodbye at the place I love the most."
Tomáš Rosický has retired from professional football.
— AC Sparta Prague (@ACSparta_EN) December 20, 2017
Details 👉 https://t.co/6jhwTxIhjz pic.twitter.com/r60VXw95Hn
Dortmund sporting director Michael Zorc told ESPN FC that Rosicky is one of the club's greatest players.
"When Tomas Rosicky was still very young, I attended a Sparta Prague match. I was there to scout a centre-back, but after Tomas had touched the ball three times I knew that I only wanted him," Zorc said.
"Tomas until this day remains one of the BVB fans' all-time favourites. His name stands for football culture, and pace. But most of all he always remained a down-to-earth and very pleasant person."
Dortmund broke the bank for the emerging midfielder in 2001, paying 25 million Deutsche Marks to Sparta as they beat a host of other top clubs to sign Rosicky.
"It makes me sick in my stomach when I hear I cost that much money," Rosicky said upon his arrival in Germany in January 2001. "Dortmund wanted me now, Bayern Munich and Liverpool only from July 1 on."
During his time with BVB, Rosicky made 149 Bundesliga appearances and scored 19 goals and won the Bundesliga title in 2002.
In 2006, Rosicky left Dortmund for Arsenal after five-and-a-half-years at the club, a move he described as "like winning the lottery."
He joined Arsenal prior to the 2006 World Cup and won the FA Cup twice.
Mesut Ozil called his former teammate a "great player" and "great character," as part of a Twitter post that read: "Congrats to a player with a big heart on a great playing career! I wish you all the best for your retirement!"
Arsene Wenger said: "If you love football, you love Tomas Rosicky," and Jack Wilshere added: "Good luck in your retirement, mate. It was an absolute pleasure to play with you. I looked up to you as a player and as a person. We spent a lot of time in the gym, unfortunately, but thank you for all the memories. I'm sure you're going to have a happy retirement, and probably go on to be a manager."
In a statement on their official website, Arsenal said: "Good luck in your retirement, Tomas. Thanks for the memories."
He also made 105 appearances for Czech Republic, scoring 23 goals and was named Czech Footballer of the Year in 2001, 2002, and 2006.